Merge branch 'topics/20642-remark-prismjs-plugin' of https://github.c…

…om/rbelow/gatsby into topics/20642-remark-prismjs-plugin

.gitignore

@@ -64,3 +64,7 @@ package-lock.json
 !themes/gatsby-starter-notes-theme/package-lock.json
 !themes/gatsby-starter-theme/package-lock.json
 !themes/gatsby-starter-theme-workspace/package-lock.json
+
+# Dev files
+.local
+.trash

packages/gatsby-plugin-mdx/utils/default-options.js

@@ -16,7 +16,7 @@ module.exports = ({ mdPlugins, hastPlugins, ...pluginOptions }) => {
       remarkPlugins: [],
       plugins: [],
       root: process.cwd(),
-      gatsbyRemarkPlugins: [],
+      gatsbyRemarkPlugins: [], // TODO:
       globalScope: `export default {}`,
       shouldBlockNodeFromTransformation: () => false,
     },

packages/gatsby-plugin-mdx/utils/get-source-plugins-as-remark-plugins.js

@@ -40,6 +40,7 @@ module.exports = async function getSourcePluginsAsRemarkPlugins({
 
   fileNodes = getNodes().filter(n => n.internal.type === `File`)
 
+  // TODO:
   // return list of remarkPlugins
   const userPlugins = gatsbyRemarkPlugins
     .filter(plugin => {

packages/gatsby-remark-prismjs/.gitignore

@@ -1,2 +1,3 @@
 /*.js
 /plugins
+/lib

packages/gatsby-remark-prismjs/src/__tests__/plugins/prism-show-invisibles-copy.js

@@ -0,0 +1,44 @@
+const loadPrismShowInvisibles = require(`../../plugins/prism-show-invisibles`)
+
+// https://artsy.github.io/blog/2018/08/24/How-to-debug-jest-tests/
+// yarn jest:inspect ./gatsby/packages/gatsby-remark-prismjs/src/__tests__/plugins/prism-show-invisibles.js
+// yarn jest ./gatsby/packages/gatsby-remark-prismjs/src/__tests__/plugins/prism-show-invisibles.js
+describe(`prism-show-invisibles`, () => {
+  test(`should export a function`, () => {
+    console.log(`here it comes:`, typeof loadPrismShowInvisibles)
+    expect(typeof loadPrismShowInvisibles).toBe(`function`)
+  })
+
+  test(`should not return`, () => {
+    expect(loadPrismShowInvisibles()).toBeUndefined()
+  })
+
+  test(`should return when global is undefined`, () => {
+    // eslint-disable-next-line no-global-assign
+    global = undefined
+    expect(loadPrismShowInvisibles()).toBeNull()
+  })
+
+  test(`should not be a mock`, () => {
+    expect(loadPrismShowInvisibles._isMockFunction).toBeFalsy()
+  })
+
+  test(`plays video`, () => {
+    const spy = jest.spyOn(loadPrismShowInvisibles, `addInvisibles`)
+    const isPlaying = loadPrismShowInvisibles.addInvisibles()
+
+    expect(spy).toHaveBeenCalled()
+    expect(isPlaying).toBe(true)
+
+    spy.mockRestore()
+  })
+
+  // TODO:
+  // [] See what I can test
+  // [] Test it!
+  // [] Debug Jest
+  // [] Export functionality?
+  // [] See how the other Prism plugins use Jest
+  // [] Jest spy
+  // [] Jest inject mock on spy
+})